Akira loves her brother's wife, Yui, like a real sister and often visits their house when she has free time. Akira can tell Yui anything and even consults her about things she can't tell anyone else, trusting her deeply. One day, while consoling Akira over a heartbreak, Yui ends up kissing her. From there, the two of them began to have a different kind of relationship... Yuu trusts and entrusts herself to Ayane.
